The present invention relates to a mounting for poles of jumps in equestrian sport, with a dish-shaped pole receiver which is suspended on a generally vertically arranged rail of a stand, wherein the receiver and the rails are connected together by means of headed bolts which extend in slots from one of the two parts to the other of the two parts, and wherein the slots have narrow slot parts with a width corresponding to approximately the width of the shaft of the headed bolt, and less than the diameter of the head of the headed bolt, and have a widened part through which the heads of the headed bolts can be inserted in order, in this way, to be able to fit the headed bolts in the slots and be able to lock them by introducing them into the narrow part of the slot.
Such pole mountings used for jumps in equestrian jumping sports have long been known. The poles, generally manufactured from wood or aluminium, with a diameter in the order of 15 cm, are placed in the correspondingly concavely configured, dish-shaped support so that if a horse jumping over the jump hits the poles horizontally with its hooves, they will be moved forwards or backwards out of the dish-shaped receiver and fall down. This happens occasionally during xe2x80x9cnormalxe2x80x9d jumping of a jump when the horse does not take off ideally such as, for example, taking off somewhat too shallow, to early or too late, or also hitting the jump with the rear hooves during jumping.
Occasionally a jump goes completely wrong, however, if the horse attempts either to stop in front of the jump at the last moment, or takes off far too early or far too late, although all of this may also be caused by mistakes on the part of the rider. In such cases, the horse may, under certain conditions, enter with its hooves deep in between the jump poles and may possibly also place a heavy load on them with the weight of its body and will then generally slip off the poles. These are relatively dangerous situations for the horse and rider which carry a considerable risk of injury.
In order to avoid this danger, rules have already been imposed for the suspension of jumps, which, inter alia, provide that the headed bolts with which the receivers are suspended on the stands must break or shear at a shearing force of approximately 800 kg. Meanwhile new regulations have also been imposed which instruct that in future the pole mounting must give way and release the pole at a vertical loading of only 140 kg.
A corresponding weakening of the headed bolts on wh ich the pole receiver is suspended would, however, significantly limit the serviceability of corresponding receivers, as loadings of 140 kg can also occur during the handling of the receivers, stands and jump poles, that is to say, for example, during the assembly and disassembly of jumps, that is to say not only when a horse jumps or enters into the jump.
With respect to the prior art, the object of the present invention is therefore to provide a mounting with the features described in the introduction, with which the criteria set out can easily be satisfied, that is to say which gives way at a pre-determined and relatively low vertical loading, so that the poles and the pole receivers are released downwards when this loading is exceeded, whereby destruction of or damage to the pole mounting will be avoided as far as possible.
This object is solved in that at the end facing away from the widened part, the slots are open and in the form of a slot section which is narrowed further compared to the narrow slot section, the width of which is dimensioned such that the bolts or bolt shafts received in the narrow part of the slot are only moveable into this narrowed section of the slot and through the open end of the slot by overcoming the pre-determined force acting in the longitudinal direction of the slot.
In contrast to the prior art, in which the headed bolts engaged in slots closed at both ends so the headed bolts could only be moved out of the slots by lifting of the heads of the bolts through the widened part, and not, however, in the longitudinal direction of the slot, the present invention provides that the slots receiving the headed bolts are open in the direction of the vertical loading occurring, but only in the form of a narrowed section of the slot which is narrower than the shaft of the bolt, so that under normal loading, that is to say under the weight of the jump pole and even when a person of normal build sits on the jump pole, said bolt cannot move into and through this narrow slot section. Only when a pre-determined loading limit is reached does the narrowed section of the slot widen out under the force of the bolt shaft pushing into this section and allow the bolt shaft to pass through, so the pole mounting is consequently released from the stand and the pole therefore falls down or is pushed downwards. In this way, the risk of injury to the horse is reduced, falls can be more easily avoided, and consequently such a situation is also less dangerous for the rider.
The rails or a corresponding section of the rails provided with the corresponding slots can, in accordance with an embodiment of the invention, be connected integrally with the pole mounting, on the side facing away from the dish-shaped pole receiver. The headed bolts would consequently be arranged on a stand and the slot would be open upwardly, so the mounting with the rail section fitted to it would be moved downwards under appropriate loading, wherein the bolts would be moved upwards, relative to the rail, out of the slots.
However, an embodiment of the invention is preferred in which the flexible connection according to the invention is effected by means of an interposed adaptor part, namely in that a conventional rail is used on a stand with a large number of vertical slots orientated one above another, in which the adaptor with headed bolts fitted to its rear side can be suspended in the usual manner at any desired height. The adaptor itself is then locked in the receiving slots of the stand, like a conventional pole support. On its side facing towards the pole support, however, the adaptor is provided with a rail or a rail section with the slot configuration according to the invention, so again, a conventional pole support can be suspended in these slots configured according to the invention of the adaptor.
The headed bolts are consequently firmly connected to the pole mounting. With this adaptor construction too, the coordination of slots and headed bolts could be reversed, in that the adaptor is provided with one or two headed bolts on its side facing towards the pole mounting, which in normal conditions of use can engage with upwardly open slots in a rail firmly connected to the receiver.
A headed bolt adaptor can also be used, that is to say a plate or a small block which has on each side one or, where necessary because of the dimensions, two or more headed bolts, wherein the headed bolts on one side could be suspended in a conventional stand rail, while the other bolt or bolts on the other side were suspended in rails provided according to the invention with one or more, in this case upwardly open, slots, on a pole mounting.
An embodiment of the invention is particularly preferred in which two bolts are provided in a mounting, provided at a vertical distance one above the other, and are fitted in particular onto the support. The headed bolts arranged one above the other at the same time in corresponding slots prevent twisting of the mounting or of the receiver about the axis of the bolt or an axis parallel to the bolt axis which would be possible if only a single bolt were used. With this configuration, it is useful, however, when only one of the two slots in which the headed bolts are received is provided with the narrowed slot section which widens out at the pre-determined force of pressure in order to allow the bolt shaft to pass through, while the other of the two slots is completely open, that is to say constantly has the width of the narrow slot section which corresponds to the thickness of the bolt shaft.
An embodiment of the invention is further particularly preferred in which the corresponding rail section is provided with two slots arranged at a vertical distance apart one above the other, for example on an adaptor, which each have a widened part, wherein the two widened parts are the same distance apart as the head of the headed bolts on the corresponding opposite piece, and wherein the two slots are either connected together by a narrowed slot section which is narrower than the width of the headed bolt shafts, or by means of a narrow slot section which corresponds to this shaft width, wherein in the latter case a corresponding narrowed, open slot section must be arranged at the end of one of the two slots opposite the slot connection.
With the variant in which the two slots are connected together by means of a narrowed slot section, an embodiment is furthermore preferred in which parallel and adjacent to the slots, and in particular adjacent to the narrowed slot section joining the two slots, additional elongate apertures are provided in the rails provided with the slots, which increase the elasticity and the capacity for movement of the walls of the narrowed slot sections.
In the preferred embodiment of the invention, the rail provided with the narrowed slot area is manufactured from a fibre-reinforced plastics material, wherein preferably the pole receiver is also composed of the same material.